Various arrangements involving two sound detectors have been suggested over the years.
An example is U.S. Pat. No. 8,259,976 where an assembly comprising a sound emitter and at least two sound detectors fixed to each other is disclosed. Each detector has a sound receiving opening. The sound receiving openings of at least two of the detectors point in opposite directions. However, there is in U.S. Pat. No. 8,259,976 no disclosure of a feedback suppression algorithm for reducing the influence of self-generated signals, such as acoustic signals and vibration signals.
It may be seen as an object of embodiments of the present invention to provide an acoustical module where the influence of self-generated signals is attenuated. Such self-generated signals may involve acoustical signals and vibration signals.